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-rw-r--r--prototypes/connections/module-text.c189
1 files changed, 0 insertions, 189 deletions
diff --git a/prototypes/connections/module-text.c b/prototypes/connections/module-text.c
deleted file mode 100644
index 68c03b0..0000000
--- a/prototypes/connections/module-text.c
+++ /dev/null
@@ -1,189 +0,0 @@
-#include "module-text.h"
-#include <math.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-enum { CHUNK = 4096 };
-
-/* state: pending continuation bytes (bits 0-1) and the allowed range of the
- * next one (bits 2-4): 0 any, 1 A0-BF after E0, 2 80-9F after ED, 3 90-BF
- * after F0, 4 80-8F after F4. */
-bool pure_utf8_step(unsigned *state, PureSpan span) {
- unsigned remaining = *state & 3, range = *state >> 2;
- for (size_t i = 0; i < span.size; ++i) {
- /* Eight ASCII bytes at a time between characters. */
- uint64_t word;
- while (!remaining && span.size - i >= 8 && (memcpy(&word, span.data + i, 8), !(word & UINT64_C(0x8080808080808080))))
- i += 8;
- if (i == span.size) break;
- unsigned char b = span.data[i];
- if (remaining) {
- unsigned low = range == 1 ? 0xA0 : range == 3 ? 0x90 : 0x80;
- unsigned high = range == 2 ? 0x9F : range == 4 ? 0x8F : 0xBF;
- if (b < low || b > high) return false;
- --remaining;
- range = 0;
- } else if (b < 0x80) {
- continue;
- } else if (b >= 0xC2 && b <= 0xDF) {
- remaining = 1;
- } else if (b >= 0xE0 && b <= 0xEF) {
- remaining = 2;
- range = b == 0xE0 ? 1 : b == 0xED ? 2 : 0;
- } else if (b >= 0xF0 && b <= 0xF4) {
- remaining = 3;
- range = b == 0xF0 ? 3 : b == 0xF4 ? 4 : 0;
- } else return false;
- }
- *state = remaining | range << 2;
- return true;
-}
-
-bool pure_utf8_complete(unsigned state) { return (state & 3) == 0; }
-
-bool pure_utf8_valid(PureSpan span) {
- unsigned state = 0;
- return pure_utf8_step(&state, span) && pure_utf8_complete(state);
-}
-
-size_t pure_utf8_scalars(PureSpan span) {
- size_t count = 0;
- for (size_t i = 0; i < span.size; ++i) count += (span.data[i] & 0xC0) != 0x80;
- return count;
-}
-
-size_t pure_utf8_newlines(PureSpan span) {
- size_t count = 0;
- for (size_t i = 0; i < span.size; ++i) count += span.data[i] == '\n';
- return count;
-}
-
-size_t pure_format_number(double value, char out[32]) {
- if (value == 0) { memcpy(out, "0", 2); return 1; }
- if (value == floor(value) && fabs(value) < 1e15) {
- /* An integer's digits, without printf (the common case, many times cheaper). */
- char digits[16];
- uint64_t n = (uint64_t)fabs(value);
- size_t count = 0, length = 0;
- do { digits[count++] = (char)('0' + n % 10); n /= 10; } while (n);
- if (value < 0) out[length++] = '-';
- while (count) out[length++] = digits[--count];
- out[length] = 0;
- return length;
- }
- for (int precision = 1; precision <= 17; ++precision) {
- snprintf(out, 32, "%.*g", precision, value);
- if (strtod(out, NULL) == value) break;
- }
- char *exponent = strchr(out, 'e');
- if (exponent) {
- char *digits = exponent + 2; /* after the sign */
- while (digits[0] == '0' && digits[1]) memmove(digits, digits + 1, strlen(digits));
- }
- return strlen(out);
-}
-
-typedef struct { unsigned char *out; } Copy;
-
-static bool copy(void *context, PureSpan span) {
- Copy *c = context;
- memcpy(c->out, span.data, span.size);
- c->out += span.size;
- return true;
-}
-
-static void read_bytes(const PureDraft *draft, PureVersion version, size_t offset, size_t length,
- unsigned char *out) {
- Copy c = {out};
- if (length) pure_draft_read_version(draft, version, offset, length, copy, &c);
-}
-
-static size_t forward(const PureDraft *draft, PureVersion version, size_t position) {
- if (position >= version.bytes) return version.bytes;
- unsigned char lead;
- read_bytes(draft, version, position, 1, &lead);
- size_t length = lead < 0x80 ? 1 : lead < 0xE0 ? 2 : lead < 0xF0 ? 3 : 4;
- return position + length <= version.bytes ? position + length : version.bytes;
-}
-
-static size_t backward(const PureDraft *draft, PureVersion version, size_t position) {
- if (!position) return 0;
- size_t take = position < 4 ? position : 4;
- unsigned char bytes[4];
- read_bytes(draft, version, position - take, take, bytes);
- size_t at = take - 1;
- while (at && (bytes[at] & 0xC0) == 0x80) --at;
- return position - take + at;
-}
-
-/* Saturating: stops at the start or end, so work is bounded by the text size. */
-size_t pure_text_step(const PureDraft *draft, PureVersion version, size_t position, double count) {
- for (; count > 0 && position < version.bytes; --count) position = forward(draft, version, position);
- for (; count < 0 && position > 0; ++count) position = backward(draft, version, position);
- return position;
-}
-
-size_t pure_text_line_start(const PureDraft *draft, PureVersion version, size_t position) {
- unsigned char chunk[CHUNK];
- while (position) {
- size_t take = position < CHUNK ? position : CHUNK;
- read_bytes(draft, version, position - take, take, chunk);
- for (size_t i = take; i-- > 0;)
- if (chunk[i] == '\n') return position - take + i + 1;
- position -= take;
- }
- return 0;
-}
-
-size_t pure_text_line_end(const PureDraft *draft, PureVersion version, size_t position) {
- unsigned char chunk[CHUNK];
- while (position < version.bytes) {
- size_t take = version.bytes - position < CHUNK ? version.bytes - position : CHUNK;
- read_bytes(draft, version, position, take, chunk);
- for (size_t i = 0; i < take; ++i)
- if (chunk[i] == '\n') return position + i;
- position += take;
- }
- return version.bytes;
-}
-
-static size_t advance_within(const PureDraft *draft, PureVersion version, size_t position,
- size_t columns, size_t limit) {
- for (; columns && position < limit; --columns) position = forward(draft, version, position);
- return position < limit ? position : limit;
-}
-
-/* Moves keep the column; with no further line the cursor goes to the end or
- * the start of the text. */
-size_t pure_text_line_step(const PureDraft *draft, PureVersion version, size_t position, double count) {
- size_t start = pure_text_line_start(draft, version, position), column = 0;
- for (size_t at = start; at < position; at = forward(draft, version, at)) ++column;
- for (; count > 0; --count) {
- size_t end = pure_text_line_end(draft, version, position);
- if (end == version.bytes) return version.bytes;
- size_t next = end + 1;
- position = advance_within(draft, version, next, column, pure_text_line_end(draft, version, next));
- }
- for (; count < 0; ++count) {
- size_t here = pure_text_line_start(draft, version, position);
- if (!here) return 0;
- size_t previous = pure_text_line_start(draft, version, here - 1);
- position = advance_within(draft, version, previous, column, here - 1);
- }
- return position;
-}
-
-typedef struct { size_t count; unsigned unit; } Count;
-
-static bool count_span(void *context, PureSpan span) {
- Count *c = context;
- c->count += c->unit ? pure_utf8_newlines(span) : pure_utf8_scalars(span);
- return true;
-}
-
-size_t pure_text_count(const PureDraft *draft, PureVersion version, size_t position, unsigned unit) {
- Count c = {0, unit};
- if (position) pure_draft_read_version(draft, version, 0, position, count_span, &c);
- return c.count + (unit ? 1 : 0);
-}